1
Thomas H Zimmerman, Julian J Pop, Joseph L Perkins: Down hole tool for determination of formation properties. Schlumberger Technology Corporation, Henry N Garrana, John H Bouchard, August 29, 1989: US04860581 (281 worldwide citation)

The apparatus of the present invention relates to a down hole tool capable of extraction of valid samples and making pressure measurements useful in calculating formation permeability. The tool incorporates the features of a staddle packing to allow formation fluid specimens to be taken at large flo ...


2
Thomas H Zimmerman, Julian J Pop, Joseph L Perkins: Down hole method for determination of formation properties. Schlumberger Technology Corporation, Henry N Garrana, Frederic C Wagret, June 26, 1990: US04936139 (230 worldwide citation)

The apparatus of the present invention relates to a down hole tool capable of extraction of valid samples and making pressure measurements useful in calculating formation permeability. The tool incorporates the features of a straddle packer to allow formation fluid specimens to be taken at large flo ...